Folding umbrella

ABSTRACT

A folding umbrella which comprises a connecting rib and a receiving rib that are held at a substantially right angle to a center rod. Said connecting rib crosses freely and slidably a support rib and the receiving rib is connected to an end rib through a sliding means. Thus, there can be provided a folding umbrella at a low cost which can be opened with a little force and folded neatly presenting a good appearance in its open position.

United States Patent 1 Kida 1 1 FOLDING UMBRELLA [76] Inventor: Nobutoshi Kids, 127 Minami Nonin-cho Higashi-ku, Osaka, Japan [22] Filed: June 23, 1972 [21] Appl. No.: 265,435

[30] Foreign Application Priority Data Oct. 21, 1971 Japan 46/96735 [52] U.S. Cl. 135/20, 135/25 [51] Int. Cl. A45b 25/14, A45b 25/16 [58] Field of Search 135/20-26 [56] References Cited UNITED STATES PATENTS 2,076,525 4/1937 Bouma 135/25 R 3,467,115 9/1969 Brooks et al 135/25 R 1 July 17, 1973 3,672,381 6/1972 Kida et al. 135/24 X FOREIGN PATENTS OR APPLICATIONS 785,872 5/1935 France 135/25 Primary ExaminerJ. Karl Bell Attorney-Woodhams, Blanchard and Flynn [57] ABSTRACT A folding umbrella which comprises a connecting rib and a receiving rib that are held at a substantially right angle to a center rod. Said connecting rib crosses freely and slidably a support rib and the receiving rib is connected to an end rib through a sliding means. Thus, there can be provided a folding umbrella at a low cost which can be opened with a little force and folded neatly presenting a good appearance in its open position.

6 Claims, 8 Drawing Figures PAIENILL- 3.746.024

sum-3 or 3 FIG] FOLDING UMBRELLA This invention relates to a folding umbrella, and more particularly to an improvement in the structure of a foldng umbrella which is capable of being collapsingly folded.

conventionally, there have been proposed various types of folding umbrellas which have a rib-structure capable of automatically collapsing when folded. For example, I have proposed such type of umbrella with a simple construction (See, US. Pat. No. 3,467,115). With such construction disclosed and claimed in the US. Pat. No. 3,467,115, however, such shortcomings can not be avoided that in preparing the rib, the length of each rib must be precisely determined and, in addition, some ribs are so short that it is difficult to process them at both ends thereof for making connecting portions thereof, leading to high cost in manufacturing.

It is therefore an object of the present invention to provide a folding umbrella which overcomes the shortcomings in the prior art as mentioned above.

It is another object of the present invention to provide a folding umbrella which can be folded neatly in a short size and can be opened smoothly with a little force.

It is a further object of the present invention to provide a folding umbrella which is economic in manufacture.

According to the present invention, there is provided a folding umbrella comprising an upper rib-holder fixed to a center rod; a running tube slidably fitted around said center rod, having a length sufficient to reach the upper rib-holder when the umbrella is opened; a lower rib-holder fixed to said running tube; an intermediate rib-holder slidably mounted on said running tube, a stop formed on said running tube to prevent the intermediate rib-holder from slipping out of the position; and a plurality of rib assemblies each comprising,

a support rib the base end of which is pivotally connected to said upper rib-holder and the lower end of which is pivotally connected to a receiving rib at its intermediate portion;

a connecting rib the base end of which is pivotally connected to said intermediate rib-holder and which crosses freely and slidably said support rib;

a connecting means pivotally connected, at its one end, to the tip end of said connecting rib and connected, at its other end, to the end rib;

an end rib the base end of which is connected to said connecting means;

a receiving rib the base end of which is pivotally connected to said lower rib-holder, a tip end being pivotally connected to a sliding means which is provided at the portion where the end rib meets with the receiving rib; and

a stop formed on the end rib to prevent said sliding means from further sliding downward than predetermined position, thereby to keep the receiving rib at a substantially right angle to the center rod when the umbrella is in its open position.

The foregoing and other objects, features and advantages of the invention may be best understood by reference to the following description taken in connection with the accompanying drawings in which:

FIG. 1 is a diagrammatical side view of a conventional folding umbrella, in its position fully opened;

FIG. 2 is a diagrammatical side view of a folding umbrella according to the present invention, in its position fully opened;

FIGS. 3A and 3B are enlarged side views each showing a part of a rib assembly of another embodiment of the present invention;

FIG. 4 is a perspective view showing the relationship between a support rib and a connecting rib of the umbrella shown in FIG. 2;

FIG. 5 is a diagrammatical side view showing the urn brella of FIG. 2, in its position almost closed;

FIG. 6 is a view explaining the dynamics of a rib assembly of a conventional folding umbrella; and

FIG. 7 is a view explaining the dynamics of a rib assembly according to the present invention.

Referring now to FIG. 1, a structure of a conventional folding umbrella is diagramatically shown, in which character a represents a center rod, character b an upper rib-holder (fixed), character c a low ribholder, character d a support rib, character e a receiving rib, character fa connecting rib and character g an end rib. An upper end of the support rib d is pivotally connected to the upper rib-holder b and a base end of the receiving rib e is pivotally connected to the lower rib-holder c. A lower end of the supportrib d is pivotally connected to the receiving rib e at its intermediate portion. A base end of the connecting rib f is pivotally connected to the support rib d at its intermediate portion. A base end of the end rib g is pivotally connected to a tip end of the connecting rib f through a connecting means and a tip end of the receiving rib e is pivotally connected to the end rib 3 near the base end thereof.

In the conventional umbrella of the kind, the rib assembly comprises the support rib, the receiving rib, the end rib and the connecting rib which are so assembled as to form a quadrilateral Q when the umbrella is opened. The length of each side of the quadrilateral must be strictly determined in order that the umbrella can be neatly folded. Accordingly, it is required to process each rib very precisely. As the connecting rib f is extremely short in the umbrella of this kind, it is difficult to process such short ribs at each end thereof for making connecting portions thereof. In addition it is required to manufacture such special short ribs, leading to high cost in manufacturing.

The conventional folding umbrella as shown in FIG. 1 and FIG. 6 has such a rib structure that in the open position of the umbrella, the receiving rib is held at an acute angle to the center rod. For opening such conventional umbrella, a considerably strong force is needed at the end of opening operation, which has made the umbrella of this type unsuitable for ladies and children. The opening operation can be facilitated by providing a substantially right angle between the receiving rib e and the center rod a as explained'in detail 4 in the following.

Referring now to the drawings, the force needed to open the umbrella at the instant of opening operation will be discussed in connection withFIG. 6 in which a receiving rib e is at an acute angle to a center rod 0 in the open position, and FIG. 7 in which a receiving rib e is at a substantially right angle to a center rod 11 in the open position.

0, designates the angle defined by the receiving rib e and the center rod a in FIG. 7, and 0 0,.designates the angle defined by the extension line of the receiving rib e and the line normal to the end rib g in FIG. 7, and 0, 90.

0, designates the angle defined by the receiving rib e and the center rod a in FIG. 6, and 0, is an acute angle.

0, designates the angle defined by the extension line of the receiving rib e and the line normal to the end rib g in FIG. 6, and 0 6 90.

There are relationships of 0, 0, and 0,' 6,'.

Assuming that F and F, designate forces needed to open the umbrella at the instant of opening operation, namely the forces normal to the end rib g, the respective component forces X and X, of the forces F and F, in the direction of the extension line of the receiving rib e are represented as follows:

X= F cosO, (FIG. 7)

Accordingly, if the force X and the force X, are exerted on the end rib g, respectively, the umbrella can be opened.

The vertical component forces Y and Y, of the forces F and F, at the center rod a, namely the forces actually needed for the user to open the umbrella, are represented as follows, considering that X and X, are the forces acting on the end rib g l= X cost), (FIG. 7)

Y, X,cos0, (FIG. 6)

Since X= F cos6,'and X, F, cos0,', it follows that Since cos9, cos I9 and cos0,' cos 0,,

it follows that F cos0,'cos6, F cos0,'cos0,.

Thus, between the forces Y and Y, which are actually needed for the user to open the umbrella, there is a relationship of Y Y,. This shows that less force is needed to open the umbrella in case a rib assembly are so constructed that the receiving rib e is held at a substantially right angle to the center rod a in the; open position.

Referring now to FIGS. 2 to 5, there is illustrated a construction of a folding umbrella according to the present invention. Numeral 1 represents a center rod, numeral 2 an upper rib-holder, numeral 3 a running tube which has a length sufficient to reach the upper rib-holder 2 when the umbrella is opened, numeral 4 a lower rib-holder fixedly fitted around said running tube 3, numeral 5 intermediate rib-holder slidably mounted on said running tube, and numeral 3a a projection formed on said running tube 3 in order to prevent said intermediate rib-holder 5 from slipping out of the posi tion. Instead of the projection, the running tube may be provided with a radially extending portion as shown in FIG. 5 at its upper portion for the same purpose. When the umbrella is in its closed position, the intermediate rib-holder is at the uppermost portion of the running tube as shown in FIG. 5. As the umbrella is opened, the intermediate rib-holder gradually moves downward to the position shown in FIG. 2. Numeral 6 represents a support rib, numeral 7 a receiving rib, numeral 8 a connecting rib, numeral 9 an end rib, numeral 9a a connecting means, numeral 9b a stop and numeral 10 a sliding means. In FIGS. 2 to 5, like parts or portions are designated with like reference numerals.

In accordance with the present invention, there is provided a folding umbrella in which a longer rib (a sliding rib) is employed as a connecting rib instead of such a short connecting rib as employed in a conventional folding umbrella. Said connecting rib 8 is not connected to the support rib 6 but crosses the support rib to extend to the intermediate rib-holder 5. A base end of said connecting rib is pivotally connected to said intermediate rib-holder 5 which is slidably provided between the upper rib-holder 2 and the lower rib-holder 4. In the thus constructed folding umbrella, the end rib, the connecting rib, the support rib and the receiving rib form the quadrilateral Q as shown in FIG. 2. At least one side of the quadrilateral Q should be variable to give the umbrella a beautiful appearance in its open position and to collapse or fold the umbrella neatly. In the present invention, a tip end of the receiving rib 7 is pivotally connected to the sliding means 10 provided at the portion where the end rib meets with the receiving rib. A base end thereof is pivotally connected to the lower rib-holder 4. The end rib 9 is pivotally connected to a tip end of the connecting rib 8 through the connecting means 9a. In FIG. 2, the sliding means'lt) is slidably titted on the end rib 9.

The receiving rib 7 is pivotally connected to said slid- .ing means 10 and the connecting rib slidably crosses the support rib. By thus making the receiving rib and the connecting rib slidable, one or more sides of the quadrilateral Q is contractile and extensible, thereby enabling the length of at least one side of the quadrilateral to be varied. Accordingly, the umbrellaican be opened smoothly with a good appearance inits open position and folded neatly in a compact size.

The support rib 6 is, as can be seen from FIG. 4, composed of two parallel rib members, an upper end of said support rib being pivotally connectedto the upper ribholder 2 and a lower end being pivotally connected to the receiving rib 7 at its intermediate portion.

Though in FIG. 4, the support rib 6 is composed of two parallel rib members and the connecting rib 8 is slidably inserted therebetween, to the contrary, the connecting rib may be composed of two parallel rib members and the support rib may be slidably inserted therebetween.

On the end rib 9, the stop 9b is formed in order to prevent the sliding means 10 from sliding further to the direction of the tip end of the end rib than the required position during the operation of opening. In addition, owing to the stop the receiving rib is kept at a substantially right angle to the center rod 1 in the open position, thereby enables the umbrella to be opened with less force than that needed for opening a conventional folding umbrella. Without the stop, the connecting rib and the receiving rib are in an unstable state.

In FIGS. 3A and 38, there are described other examples for a rib assembly according to the present invention. The connecting means'9a is pivotally connected to a tip end of the connecting rib 8 and a tip end of the receiving rib is pivotally connected to the sliding means 10 which is a part of said end rib 9 or an extension integrally formed with the end rib 9 at its base portion. In FIG. 3A, the end rib 9 with the sliding means 10 is telescopically fitted to the connecting means 9a. 0n the contrary, the end rib 9 with the sliding means 10 may be telescopically fitted to the connecting means as shown in FIG. 3B. In'this case, the connecting means has a narrow groove at the lower side thereof for guiding the connecting portion of the receiving rib with the sliding means.

By providing the folding umbrella according to the present invention, all of the objects stated above can be thoroughly accomplished.

What is claimed is:

1. A folding umbrella comprising an upper rib-holder fixed to a center rod; a running tube slidably fitted around said center rod, having a length sufficient to reach the upper rib-holder when the umbrella is opened; a lower rib-holder fixed to said running tube; an intermediate rib-holder slidably mounted on said running tube, a stop formed on said running tube to prevent the intermediate rib-holder from slipping out of the position; and a plurality of rib assemblies each comprising,

a support rib the base end of which is pivotally connected to said upper rib-holder and the lower end of which is pivotally connected to a receiving rib at its intermediate portion;

a connecting rib the base end of which is pivotally connected to said intermediate rib-holder and which crosses freely and slidably said support rib;

a connecting means pivotally connected, at its one end, to the tip end of said connecting rib and connected, at its other end, to the end rib;

an end rib the base end of which is connected to said connecting means; a receiving rib the base end of which is pivotally connected to said lower ribholder, a tip end being pivotally connected to a sliding means which is provided at the portion where the end rib meets with the receiving rib; and

a stop formed on the end rib to prevent said sliding means from further sliding downward than predetermined position, thereby to keep the receiving rib at a substantially right angle to the center rod when the umbrella is in its open position.

2. A folding umbrella according to claim 1, wherein said support rib is composed of two parallel rib members and said connecting rib crosses freely and slidably said support rib between said two parallel members thereof.

3. A folding umbrella according to claim 1, wherein said connecting rib is composed of two parallel rib members and said support rib crosses freely and slidably said connecting rib between said two parallel members thereof.

4. A folding umbrella according to claim 1, wherein said sliding means is slidably fitted on said end rib.

5. A folding umbrella according to claim'l, wherein said sliding means is an extension of the end rib integrally formed at its base portion and is telescopically fitted to said connecting means.

6. A folding umbrella according to claim 1, wherein said sliding means is an extension of the end rib integrally formed at its base portion and is slidably inserted in said connecting means which has a narrow groove at the lower side thereof for guiding the connecting portion of the receiving rib with the sliding means. 

1. A folding umbrella comprising an upper rib-holder fixed to a center rod; a running tube slidably fitted around said center rod, having a length sufficient to reach the upper rib-holder when the umbrella is opened; a lower rib-holder fixed to said running tube; an intermediate rib-holder slidably mounted on said running tube, a stop formed on said running tube to prevent the intermediate rib-holder from slipping out of the position; and a plurality of rib assemblies each comprising, a support rib the base end of which is pivotally connected to said upper rib-holder and the lower end of which is pivotally connected to a Receiving rib at its intermediate portion; a connecting rib the base end of which is pivotally connected to said intermediate rib-holder and which crosses freely and slidably said support rib; a connecting means pivotally connected, at its one end, to the tip end of said connecting rib and connected, at its other end, to the end rib; an end rib the base end of which is connected to said connecting means; a receiving rib the base end of which is pivotally connected to said lower rib-holder, a tip end being pivotally connected to a sliding means which is provided at the portion where the end rib meets with the receiving rib; and a stop formed on the end rib to prevent said sliding means from further sliding downward than predetermined position, thereby to keep the receiving rib at a substantially right angle to the center rod when the umbrella is in its open position.
 2. A folding umbrella according to claim 1, wherein said support rib is composed of two parallel rib members and said connecting rib crosses freely and slidably said support rib between said two parallel members thereof.
 3. A folding umbrella according to claim 1, wherein said connecting rib is composed of two parallel rib members and said support rib crosses freely and slidably said connecting rib between said two parallel members thereof.
 4. A folding umbrella according to claim 1, wherein said sliding means is slidably fitted on said end rib.
 5. A folding umbrella according to claim 1, wherein said sliding means is an extension of the end rib integrally formed at its base portion and is telescopically fitted to said connecting means.
 6. A folding umbrella according to claim 1, wherein said sliding means is an extension of the end rib integrally formed at its base portion and is slidably inserted in said connecting means which has a narrow groove at the lower side thereof for guiding the connecting portion of the receiving rib with the sliding means. 